Switch blade



p 1957 A. A. ALLEN 2,806,927

- swncu BLADE Filed June 7, 1955 ]NVENTOR.

H AIL/W ,4. ALLEN Patented Sept. 17, 1957 SWETCH BLADE Alan A, Allen, Beverly Hills, Calif.

Application June 7, 1955, Serial 513,733

(Jlaims. (ill. 299-471) This invention relates to a switch blade construction of the type used in snap switches. The blade is of the general type shown in Pat. No. 2,511,526 and is an improvement on the blade disclosed in said patent.

It is an object of this invention to provide an improved switch blade which is stressed in such a manner as to set up a deformation which, upon being subjected to a small movement at one area or section, will impart to another area or section a rapid and substantially larger movement or displacement.

Another object of the invention is to provide inexpensive and simplified means for holding the blade in the mentioned stressed condition.

The present blade construction comprises a hardened flat spring and a relatively softer contact element, it being a further object of the invention to provide improved means that utilizes said contact element as the blade stressing means.

The foregoing and other objects, features and advantages of the invention will become more clearly evident from the following detailed description of a preferred form of the invention, the same having basis on the accompanying drawing in which like numerals designate similar parts in the several views.

In the drawing:

Fig. 1 is a plan view of a switch blade embodying the features of the present invention.

Fig. 2 is a longitudinal sectional view thereof as taken on line 2--2 of Fig. 1.

Fig. 3 is an enlarged fragmentary plan view of the right hand end of the switch blade as in Figs. 1 and 2.

Fig. 4 is a cross-sectional view as taken on line 44 of Fig. 3.

Fig. 5 is a plan view showing the spring blade of said switch blade in unstressed condition and the manner of assembly of the stress-holding contact.

Fig. 6 is a cross-sectional view similar to Fig. 4 before the blade is stressed and finally assembled, as in said Fig. 4.

The present switch blade construction comprises, generally, a spring blade 16, and a combined contact element and blade-stressing means 11.

The blade 10 is formed of hard spring metal having suitable resilience and electric conductivity. Said blade is initially formed to have a generally rectangular shape, as in Fig. 5, and, at one end, is provided with an end-open slot 12 that defines similar spring arms 13. As shown, slot 12 has substantial width. Near the open end of the slot, the inner edges of the arms are provided with complementary and preferably semi-circular indentations 14 that, when brought together, form a circular opening in the bifurcated spring blade end. Each arm 13, in substantial alignment with indentation 14 therein, is provided with a hole 15. The opposite end of the blade may be provided with a hole 16 for a fastening screw or the like for securing the blade as to a platform 17 (Fig. 2).

The combined contact element and blade-stressing means 11 is preferably initially formed as a member shaped like a dumb-bell and having good electrical-conducting properties. Hard tempered fine silver is an example of the metal of which said element may be for-med. The same, while hard tempered is yet relatively soft and is capable of being formed after assembly, as desired.

As seen in Fig. 6, element 11 is initially formed to have spaced contact flanges 18 that are connected by a preferably cylindrical neck 19 that is approximately diametrally the size of the circular opening formed by indentations 14 when brought together. The diametral size of flanges 13 is such that the marginal portions thereof overstand at least part of the holes 15 when arms 13 are brought together, as in Figs. 1, 3, and 4.

While the size of spring blade 10 may vary considerably, the same, from the center of hole 16 to the bifurcated end, may be in the nature of one-half inch in blades used in miniature switches. Hence, it will be seen that the arms 13 may readily be brought together, after element 11 has been placed in the dot-dash line position of Figs. 5 and 6 and, while so held, suitable tool or die means may be employed to swage the flanges 18 into the holes 15 to form key portions 20 that reside in said holes, as in Fig. 4. While thus swaging the key portions 24) into holes 15, the die means may, at the same time, impart a convex form to said flanges, as shown at 21.

Since key portions 20 effectively retain the spring arms 13 in their stressed position, the blade may be flexed many times with complete assurance that said arms will not become loosened from element 11.

From Fig. 2 it will be seen that the actuator 22, by being pressed against the opposed lateral portions 23 of the blade (Fig. 1), will transversely flex said blade over platform 17 to cause the bifurcated end of the blade and the element 11 thereon to flex longitudinally in a downward direction from the position of Fig. 2. Upon release of actuator 22, the blade returns to the position of Fig. 2.

Since variations may be made in the present means that would fall within the scope of the invention, I wish to reserve to myself all such variations and modifications that fall within the spirit and scope of the appended claims.

' I claim:

1. A switch blade comprising a flat spring blade having an end-open slot defining spring arms, said arms, adjacent their free ends, having openings formed therein, and a contact element in the slot and having portions in overstanding relation to said openings, said overstanding contact element portions extending into said openings.

2. A switch blade according to claim 1: the free ends of said arms being flexed toward each other on opposite sides of the contact element.

3. A switch blade according to claim 1: said contact element being provided with spaced contact flanges and a connecting neck portion, and said arms, adjacent their free ends, having opposed indentations formed therein, said arms being flexed toward each other, and the indentations, when the arms are so flexed, accommodating the mentioned contact element neck portion.

4. In a switch blade having spaced spring arms and the arms being flexed to bring the free ends thereof toward each other, each arm having an opening therein, a contact element disposed between the free ends of the arms and provided with portions overstanding said openings and partly entered into said openings to key lock the spring arms in the mentioned flexed position.

5. In a switch blade according to claim 4: the opposed edges of the arms having complementary indentations therein that define an opening, and the mentioned overstanding portions of the contact element being connected by a neck portion residing in the opening defined by the complementary indentations.

References Cited in the file of this patent UNITED STATES PATENTS 

